Automatic draft regulator for orchard heaters



1944- J. F. MAHLSTEDT' 2,36 8

AUTOMATIC DRAFT REGULATOR FOR ORCHARD HEATERS Filed Nov. 19, 1940 2 Sheets-Sheeii 1 -1 ii I 15 12 13 16 22 A o o o o 9- J4 I ATTORNEY NOV. 7, 1944. J. H ST 2,362,285

AUTOMATIC DRAFT REGULATOR E01 ORCHARD HEATERS 7 Filed Nov. 19,1940

Sheets-Sheet 2 Patented Nov. 7, 1944 2,362,285M I AUTOMATIC DRAFT REGULATORJFOR i ORCHARD HEATERS; John Frederiok'Mahlstedt, Los"Angele's;'Calif.;-as-

signer :tov Scheu Products. CompanmaLtd Hi.

Uplandtrcalifaa corporation .of Galiforniaza a l ApplicationNovember 19, 1940, Serial mascara 3Claims. (01,158 91);

My resentginvention relates to. an automatic draft regulating means for orchard heaters.

One .Ofjh principal oblectsof this inventionis to provide .an. automatic draft re ulatingmeans of this class which -.is p rticularly. simp e and economical of construction, one whi'chuls easyto adjust .and-operate, and'one which. is. foolproof in its operation and. whichwillrnot. readily deteriorate... v

Another important objector this invention, is to provide adraft regulator. of thisclasswhich maybe readily installed on orchard heaters now in use, land tspecifically'on the filling openingcaps or themanual.draftlregulating capsnow. in use thereon; v

An irhportelntbbject alsoofi this invention is to provide an automatic. draft-regulating-means ,of this class in which the draft opening isclosed 'by a thermostat and in which theforce, for closingthe draft opening,t whichithermostat is subjected, is reducedto, a minimum, therebydecreas- 'ing anormal tendency oi distorting, the thermosstat..whnponstantly.subjected to heat and resistance. r I

A further important. object of this invention is to provide a'draft regulatorwhich is fautomatically adjusted toa predetermined closed position, butwhich maybe subsequently manually adjusted .by substantiallythasame means. p

Still another important object of, this'invention is toprovide simple cam means for manually. reg;- atingithedraft opening, I A stilltfulfth r importantobjectof, this invention is to provide a draft regulator on an orchard heater and which is arranged for automatiodraft regulation on or. in connection with thefuel filling opening thereof. With these andother objects in view, asv will appearhereinafter; 'I--have "devised an automatic draftcregulator f0r orchard heaters, which consists of certain novelsfeatures of construction, combination, and arrangement of parts-and' portionSn-as, willube. hereinafter. described in detail andparticularlytset forth inpthe appended claims, reference beinglhad to, the accompanying drawe ings and, to. thepharacters of reference thereon, which .form a part of vthisiailtolication, in which: FigI'l is'a fragmentary side elevation of an orchard heater showing my draft regulating means-thereon?" Fig.--4,.i,s an enlarged; fragmeh amview in' Plan of my draft-regulating means inan open. position;

Fig; 5 is a sectionalviewthereof,taken through 55 of Fig. 2;

,1 Fig. 6is afragmentary planlview, similarto Fig. 2, of a modified ,form; a

Fig. 7 is a fragmentary. section. thereof, ,taken through..f|,'l-of Fig. 63, I

Fig. dis a fragmentary:sectionaLelevation,

takenthrough 8-8-of Fig.: 7, showing therrelation of ,thetshutter to the draft regulating, there mostatrand v v Fig. ,9 is a, fragmentary ,sectionaltelevation, taken through 9.9; of Fig. 7, showing the manual meansfor regulating the draft. i

The; draft regulator or regulating meanspfmy invention. iseshowneon or in connectionwitha Fig.2 is anlenlargedfragmentary plan view of conventional; type, orchard heater. The, heater shown-consists.- of a fuel receptacle 1, acoverl for covering substantially thewhole-of; the upper part of the receptacle, and-a stack :3 which rises centrally. above the .cover.

The cover in the conventional orchard heater, as shown ill/the. drawings,-is.-.providedwith a draft 3 Il iin thecapfor manually regulatingthe amount'of air which is to pass through the cap into the receptacle When-"the opening 13 is outof registry with' theopening'l 1*, air isexcluded from the receptacle. "The full open and closed positions are determined by suitable stops. These stops-may be shoulders l3 and 13'' on the shutter 13 which may-engage the opposite 1 edges of the plate l 2 ofthe hinge I2, as shown in- Figs. 3 and-2 v To the-upper side of the shutter I3 is secured a strap [4 whi'ch forms a handle for rotating the shutter with respect to the cap., One end of the strap extends beyondthe shutter and is adapted handle M. The plate may be directly pivoted on this handle, or it may be pivoted at one edge of the hinge plate 22, as shown in the drawings, this plate 22 being secured to the shutter, preferably above or to the upper side of the handle H. The shutter I3 is preferably frictionally connected with the axial portion of the cap H by means of a pivot bolt l6 and a spring H, the latter being positioned around the bolt above the shutter. This bolt 16 extends preferably through the plate 22 and the spring I! is preferably located above the hinge plate 22.

At the inner or under side of the cap is a bimetal thermostat 3| which is supported at one end on a bracket 32 secured to the under side of the cap I in such a manner that the free end of the thermostat extends towards the side of the cap at which the free end of the handle I4 is located. The draft regulating plate-2| has a lug 2| which extends to the opposite side of the pivotal axis from the main portion'of the plate 2|, and is bent slightly downwardly from the plate of the main portion of the plate 2 When the plate 2| is in a closed position, as shown by solid lines in Fig. 5 of the drawingsthe lug 2| engages the inner side of the free end of the thermostat, the shutter |3, handle l4, and the plate 22 being provided Withsuitable openings to allow the lug 2 l to project from the upper to the lower side of these members.

When the thermostat is subjected to heat, as when the heater is lighted and burning properly, the thermostat 3| is distorted, as shown in dotted lines in Fig. 2, forcing thelug backwardly and the plate 2| about its pivotal axis until the plate is over-balanced and falls by gravity to a closed position over the aforementioned draft opening.

. Near the free edge of the plate 2| is a regulating member 4|, which in this instance is a screw which may be locked in its adjusted position by a lock nut 42. The one or free end of the adjusting screw extends beyond the underside of the plate 2| and is adapted to engage the top side of the shutter l3 for limiting the closed position of the draftregulating plate 2|.

The provision of the automatic draft regulating means on the cap and shutter does not interfere with the manual control of the shutter with respect to the cap. To effect such manual radjustment, I have, provided an inclined or spiral cam 43 at the normally underside of the plate 2|. This cam is preferably located at the end opposite the lug 2|. Slight counter-clockwise rotation of the shutter will cause the cam to engage the cap adjacent the vent hole H and cause the plate 2 Mo be raised as the shutter is rotated. It will be noted that before manual rotation or shifting of the shutter, the cam 43 extends freely downwardly into. the vent openings I? and I3 The shutter is rotated by means of the, handle |4. If desired, the draft regulating plate 2| may beutilted backwardly out of the way to permit only, the manual control for the draft, which is effected by closing the draft opening I I.

The thermostat 5| extends diametrically across the cap H and is secured at one end to a plate 52 which spaces the thermostat below the underside of the cap I The draft regulating plate 2|, in this instance, has a downwardly extending lug 53, which lug is positioned at the same side from the pivotal axis of the draft regulating plate 2| as the main portion of the plate. In its normal .position, that is, when the heater is cold or is about to be lighted, the end of the lug 53 rests upon the upper side of the free end of the thermostat and thereby holds the plate 2| in a maximum open position, as shown in Fig. 8.

When the heater is lighted and continues to burn, the thermostat is heated and is deflected downwardly by the heat, allowing the plate to assume a predetermined open position for normal burning of the heater, as'shown by dotted lines in Fig. 8.

When desiring to open the draft regulating plate beyond its predetermined position, which is controlled by the screw 4|, the shutter I3 is rotated counter-clockwise by means of the handle Hi. When so rotated, an inclined cam 54, also provided at the underside of the draft regulating plate 2|, engages one end of the draft opening I I and raises the plate 2| about its pivotal axis in proportion to the rotation of the shutter, as shown best in Fig. 9. It will be noted that the plate 2| is raised about its pivotal axis by the inclined cam 54 only beyond the normally open position determined by the screw 4 It will be noted that the lug 53 is inclined at its inner edge, as indicated by 53 This inclined edge, when the shutter and the draft regulating plate thereon are rotated counter-clockwise, forces the lug 53 to rise and to mount the free end of the thermostat, that is, to assume its inital position.

Though I have shown and described a particular construction, combination, and arrangement of parts and portions, and certain modifications thereof, I do not wish to be limited to the same, but desire to include in the scope of my invention the construction, combination, and arrangement substantially as set forth in the appended claims.

I claim:

1. In a heater having a combustion chamber and a vent opening, a shutter rotatably mounted on the heater to cover and uncover the vent opening, a draft regulating plate hingedly mounted on a substantially horizontal axis on the shutter and disposed adjacent and adapted variously to cover said opening in a position to restrict the passage of air therethrough, means in connection with the plate for positively limiting the closed position of the plate over the opening, and a cam onthe plate, said camadapted variously to engage'the heater adjacent the vent opening for-determining the open position of the plate, above the position determined by said means, when'the shutter is rotated to various positions.

2. In a heater having a combustion chamber and a vent opening, a shutter rotatably mounted on the heater .to .coverand uncover the vent opening, a draft regulating plate hingedly mounted on a substantially horizontal axis on the shutter and adapted normally to be held in an open position with respect to the shutter, and a cam on the shutteradapted variously to engage the heater adjacent the vent opening therein for holding the plate in various open positions dependent upon the rotated position of the shutter.

3. In association with a vaporizing type or.- chard heater provided with a vaporizing chamber, said heater having a cover over the vaporizing chamber and provided with an air-admitting opening for maintaining a vaporizing flame within said heater, a cap on the cover to close over the opening and providedwith a vent, a shutter axially mounted onthe cap and provided with a registering vent, a draft regulating plate pivoted on a substantially horizontal axis on the shutter and adapted normally to be held in an open popendent upon the rotated position of the shutter with respect to'the cap.

JOHN FREDERICK MAHLSTEDT. 

